Influence of SiO_2/Al_2O_3 Content on Structure and Hydration Activity of Granulated Blast Furnace Slag

摘要

Granulated blast furnace slag (GBFS) is a by-product of manufacturing iron. Samples of GBFS with different ratio of SiO_2/Al_2O_3 were prepared by simulating the actual process of GBFS in laboratory. This study investigated the influence of SiO_2/Al_2O_3 content on structure and hydration activity of GBFS which were characterized by X-ray fluorescence (XRF), powder X-ray diffraction (XRD), infrared radiation (IR) and mechanical testing. It is found that the vitreous content of each sample is above 97% and the hydration activity indexes of 7D and 28D of samples significantly decrease with the increase of SiO_2/AI_2O_3 ratio. The IR characteristic absorption spectrum shows that the silicates mainly exist in [SiO^-tetrahedra and the aluminum atoms are in different coordination states and the bonding strengths rise with the increase of SiO_2/AI_2O_3 ratio.